arm-bsp/n1sdp: Use git clone to fetch FW for the N1SDP

git.linaro.org/landing-teams/working no longer seems to serve snapshots
in tar.gz format, breaking the N1SDP build for kirkstone.

Using same tag as the existing snapshot, fetch the binaries with a
conventional git clone, as per master.

Signed-off-by: Adam Johnston <adam.johnston@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

meta-arm-bsp/recipes-bsp/images/n1sdp-board-firmware_2020.07.27.bb

@@ -11,10 +11,11 @@ INHIBIT_DEFAULT_DEPS = "1"
 PACKAGE_ARCH = "${MACHINE_ARCH}"
 COMPATIBLE_MACHINE = "n1sdp"
 
-SRC_URI = "https://git.linaro.org/landing-teams/working/arm/n1sdp-board-firmware.git/snapshot/${BPN}-N1SDP-${PV}.tar.gz"
-SRC_URI[sha256sum] = "57feba404026f2d6d49c167d63e0e84653ad8b808b13e2244b81fea9e0d58d66"
+SRC_URI = "git://git.linaro.org/landing-teams/working/arm/n1sdp-board-firmware.git;protocol=https;branch=master"
 
-S = "${WORKDIR}/${BPN}-N1SDP-${PV}"
+SRCREV  = "9a095cbdf8ef59a7433e2769e4e2e92782b68c50"
+
+S = "${WORKDIR}/git"
 
 INSTALL_DIR = "/n1sdp-board-firmware_source"